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Original poster

Help! I put petrol in diesel car

138 replies

WhatdoIdoooooo · 15/08/2024 14:22

Nightmare.

Just been to the petrol station, car was on v low no petrol (I know I know)
Our car has been in the garage for a while, so we’ve had a hire car-a petrol one (ours is Diesel)
I only had enough in my purse to put €10 in and by accident I put petrol in, instead of Diesel. Thankfully I realised my mistake when I was putting the pump back and didn’t start the car.
I went in to ask for help, they recommended I go to the garage nearby, then saw it was shut for lunch, I had to move my car out of the way, so people would have to help push 😩
The woman there said I hadn’t put much petrol in so if I was to put a lot of Diesel in it might be ok. I managed to convince them to let me put €50 in so I could drive home and get the €50 and bring it back to them. The car started and I managed to do this, car was running ok, is the car ok now??? Or do I need to do more? Have messsged Dh but he’s at work and hasn’t seen the message yet

OP posts:
Soshu · 15/08/2024 14:25

This happened to me but I’d put around £30 in. Car started to judder as soon as I drove off. Had to call one of those specialists out at a cost of nearly £300

SquirrelRed · 15/08/2024 14:26

I know next to nothing about cars so please bare that in mind but my partner has done this before, and just put double the amount of diesel in and it was fine so fingers crossed you'll be ok

madamim · 15/08/2024 14:27

I've done this.

Fill tank to full with diesel, when tank is half full fill up again, repeat for a few weeks. It will dilute the petrol down.

Needanewname42 · 15/08/2024 14:28

I'd fill it up with deseil, and hopefully it will be OK. I think you'd know if their was an issue.

It's actually more serious to put deseil in a petrol car.

Boopbeepbeepboop · 15/08/2024 14:28

I think putting a little petrol into a diesel by accident and then filling with diesel, can be ok. But diesel into a petrol is a no no. But I might have just read that somewhere 🤣

LetMeGoogleThat · 15/08/2024 14:29

Ex husband filled the tank of my petrol car with diesel, I hadn't realised it ran for 5 mins and juddered to a halt. Needed to be towed by the AA and have a tank flush. Not the main reason he's the ex tho!

rewilded · 15/08/2024 14:31

I have put diesel in a petrol and got a few metres and it died. It cost a fortune to flush and was never the same again. I did put half a tank in though.

Molecule · 15/08/2024 14:33

Back in the old days (no idea when) they used to put a bit of petrol into diesel vehicles to stop the diesel freezing (no idea of the ratio) so it’s not the worst thing you can do. As @Needanewname42 says, diesel into a petrol car is far worse - exh (car trade all his life) did it to my car, drove off and after a few miles the engine burst into flames.

Needanewname42 · 15/08/2024 14:34

It's now quite hard to fill a petrol with deseil. The diesel nosels are too big for petrol cars.

And it was done that way because a diesel engine can cope with petrol but petrol engine can be badly damaged by diesel

Original poster
WhatdoIdoooooo · 15/08/2024 14:40

Dh is going nuts ffs

OP posts:
Boopbeepbeepboop · 15/08/2024 14:41

WhatdoIdoooooo · 15/08/2024 14:40

Dh is going nuts ffs

What's that going to achieve?!

Magnastorm · 15/08/2024 14:42

What you should have done is pushed the car out of the way and gotten the tank drained without starting it. Often your insurance will cover the cost of having a tank drained in the event of a mis-fuel because obviously that's a far better option than repairing the damage it can cause.

Diesel cars use the fuel as a lubricant; putting petrol in there can cause the lubricant to dissolve, resulting in damage to the fuel lines and the fuel pump amongst other things. You need to take it to a garage and hope nothing has got too badly damaged.

lanthanum · 15/08/2024 14:44

Needanewname42 · 15/08/2024 14:34

It's now quite hard to fill a petrol with deseil. The diesel nosels are too big for petrol cars.

And it was done that way because a diesel engine can cope with petrol but petrol engine can be badly damaged by diesel

Sometimes I think that there should be more public recognition of people who come up with ideas like this.

Newname71 · 15/08/2024 14:46

Have you checked your car insurance? One of my policies covered for this.

Thatnameistaken · 15/08/2024 14:48

It'll be absolutely fine at that diesel/petrol ratio, my husband put £20 worth in once, we brimmed it with diesel and it was fine.

SlightlygrumpyBettyswaitress · 15/08/2024 14:49

I was told by AA that if it was only a few litres, to do what you did and fill it up.
Sadly I had filled mine from empty to full! It's a mistake you only make once.

Goodadvice1980 · 15/08/2024 14:49

Bad idea to start the car 🥴 it’s much safer and easier to just drain the tank containing the wrong fuel.

Needanewname42 · 15/08/2024 14:49

How much petrol does it take to damage a diesel engine?

As a safe amount some car manufacturers will say none though the industry generally accepts 7.5% or less of petrol in diesel is safe. When you work it out for your tank capacity you will soon realise it's not a lot of the wrong fuel before it's too much.

A quick Google brings up this. I'd do as previous poster and the petrol station suggested, keep topping it up with diesel to dilute the petrol.
And cross your fingers no real damage is done.

Original poster
WhatdoIdoooooo · 15/08/2024 14:53

@Boopbeepbeepboop Probably just to make me feel crap/be angry!

OP posts:
Janek · 15/08/2024 14:54

I did this once to my uncle's car in similar circumstances - we'd borrowed a petrol car and returned it, so I was driving his. It was low on fuel so we went to a local, expensive petrol station and put in a few litres of petrol, to keep us going till we could go somewhere cheaper. It wasn't until the next day when I realised the 'remaining mileage' had gone a bit crazy that I realised what I'd done. We went straight to the petrol station and filled it with diesel (and this was a bit of a drive as we were in rural France), but the car seemed fine afterwards. In fact it might have been running a bit better, but that might just be wishful thinking...

Obviously we confessed all to my uncle, but there were no consequences. We must have driven at least twenty miles on low diesel/small amount of petrol mix before we could rectify it.

BashfulClam · 15/08/2024 14:59

The correct thing is what you did, fill it with diesel to dilute the petrol. I did that once, I only realised as I got to about £10 and freaked out. There was a workshop round the bs j and the mechanic came round and said ‘ach just fill it right up with diesel and I guarantee you’ll be awright’ he was right. Never had a problem with it after that.

Tell your husband to shut up, I bet he’s not perfect…tit!

Original poster
WhatdoIdoooooo · 15/08/2024 15:03

Dh says I should fill the engine up completely with diesel?

OP posts:
Seashor · 15/08/2024 15:04

With that small amount of petrol you’ll be fine. It might chug a bit but not for long. My son did it, there was no damage.

dbeuowlxb173939 · 15/08/2024 15:04

Boopbeepbeepboop · 15/08/2024 14:28

I think putting a little petrol into a diesel by accident and then filling with diesel, can be ok. But diesel into a petrol is a no no. But I might have just read that somewhere 🤣

This is true. The fact that you've managed to drive ok is a good sign. I would fill the tank up with diesel and keep doing that so you're diluting the petrol out

dbeuowlxb173939 · 15/08/2024 15:06

WhatdoIdoooooo · 15/08/2024 14:40

Dh is going nuts ffs

Idiot, has he never made a mistake?

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